Tank crashed, will Zoas recover?

[mechengr]

Hey all, I did a bonehead move and during a water change, I cleaned my sponge filter, which I hadn’t done in a while. Well, my nitrates and phos dropped from about 10 and .2 to .4 and .03 overnight. Well, my corals didn’t like that at all. It bleached one, caused another to slime up and my zoas closed (2 of 3 varieties). It’s been two weeks and my numbers are climbing again but the zoas still are closed. They don’t look like they are dying, but how long will it take for them to open again?
40 gal mixed reef, all other parm’s are in range.

 

[Hemmbone20]

you sure that’s the cause? I wouldn’t assume it was due to cleaning the sponge… I would double check the water you used for your water change. Where did you get it?